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Diffstat (limited to 'numeric.c')
-rw-r--r-- | numeric.c | 691 |
1 files changed, 691 insertions, 0 deletions
diff --git a/numeric.c b/numeric.c new file mode 100644 index 0000000000..a22f813e64 --- /dev/null +++ b/numeric.c @@ -0,0 +1,691 @@ +/* numeric.c + * + * Copyright (c) 2001, Larry Wall + * + * You may distribute under the terms of either the GNU General Public + * License or the Artistic License, as specified in the README file. + * + */ + +/* + * "That only makes eleven (plus one mislaid) and not fourteen, unless + * wizards count differently to other people." + */ + +#include "EXTERN.h" +#define PERL_IN_NUMERIC_C +#include "perl.h" + +U32 +Perl_cast_ulong(pTHX_ NV f) +{ + if (f < 0.0) + return f < I32_MIN ? (U32) I32_MIN : (U32)(I32) f; + if (f < U32_MAX_P1) { +#if CASTFLAGS & 2 + if (f < U32_MAX_P1_HALF) + return (U32) f; + f -= U32_MAX_P1_HALF; + return ((U32) f) | (1 + U32_MAX >> 1); +#else + return (U32) f; +#endif + } + return f > 0 ? U32_MAX : 0 /* NaN */; +} + +I32 +Perl_cast_i32(pTHX_ NV f) +{ + if (f < I32_MAX_P1) + return f < I32_MIN ? I32_MIN : (I32) f; + if (f < U32_MAX_P1) { +#if CASTFLAGS & 2 + if (f < U32_MAX_P1_HALF) + return (I32)(U32) f; + f -= U32_MAX_P1_HALF; + return (I32)(((U32) f) | (1 + U32_MAX >> 1)); +#else + return (I32)(U32) f; +#endif + } + return f > 0 ? (I32)U32_MAX : 0 /* NaN */; +} + +IV +Perl_cast_iv(pTHX_ NV f) +{ + if (f < IV_MAX_P1) + return f < IV_MIN ? IV_MIN : (IV) f; + if (f < UV_MAX_P1) { +#if CASTFLAGS & 2 + /* For future flexibility allowing for sizeof(UV) >= sizeof(IV) */ + if (f < UV_MAX_P1_HALF) + return (IV)(UV) f; + f -= UV_MAX_P1_HALF; + return (IV)(((UV) f) | (1 + UV_MAX >> 1)); +#else + return (IV)(UV) f; +#endif + } + return f > 0 ? (IV)UV_MAX : 0 /* NaN */; +} + +UV +Perl_cast_uv(pTHX_ NV f) +{ + if (f < 0.0) + return f < IV_MIN ? (UV) IV_MIN : (UV)(IV) f; + if (f < UV_MAX_P1) { +#if CASTFLAGS & 2 + if (f < UV_MAX_P1_HALF) + return (UV) f; + f -= UV_MAX_P1_HALF; + return ((UV) f) | (1 + UV_MAX >> 1); +#else + return (UV) f; +#endif + } + return f > 0 ? UV_MAX : 0 /* NaN */; +} + +#if defined(HUGE_VAL) || (defined(USE_LONG_DOUBLE) && defined(HUGE_VALL)) +/* + * This hack is to force load of "huge" support from libm.a + * So it is in perl for (say) POSIX to use. + * Needed for SunOS with Sun's 'acc' for example. + */ +NV +Perl_huge(void) +{ +# if defined(USE_LONG_DOUBLE) && defined(HUGE_VALL) + return HUGE_VALL; +# endif + return HUGE_VAL; +} +#endif + +NV +Perl_scan_bin(pTHX_ char *start, STRLEN len, STRLEN *retlen) +{ + register char *s = start; + register NV rnv = 0.0; + register UV ruv = 0; + register bool seenb = FALSE; + register bool overflowed = FALSE; + + for (; len-- && *s; s++) { + if (!(*s == '0' || *s == '1')) { + if (*s == '_' && len && *retlen + && (s[1] == '0' || s[1] == '1')) + { + --len; + ++s; + } + else if (seenb == FALSE && *s == 'b' && ruv == 0) { + /* Disallow 0bbb0b0bbb... */ + seenb = TRUE; + continue; + } + else { + if (ckWARN(WARN_DIGIT)) + Perl_warner(aTHX_ WARN_DIGIT, + "Illegal binary digit '%c' ignored", *s); + break; + } + } + if (!overflowed) { + register UV xuv = ruv << 1; + + if ((xuv >> 1) != ruv) { + overflowed = TRUE; + rnv = (NV) ruv; + if (ckWARN_d(WARN_OVERFLOW)) + Perl_warner(aTHX_ WARN_OVERFLOW, + "Integer overflow in binary number"); + } + else + ruv = xuv | (*s - '0'); + } + if (overflowed) { + rnv *= 2; + /* If an NV has not enough bits in its mantissa to + * represent an UV this summing of small low-order numbers + * is a waste of time (because the NV cannot preserve + * the low-order bits anyway): we could just remember when + * did we overflow and in the end just multiply rnv by the + * right amount. */ + rnv += (*s - '0'); + } + } + if (!overflowed) + rnv = (NV) ruv; + if ( ( overflowed && rnv > 4294967295.0) +#if UVSIZE > 4 + || (!overflowed && ruv > 0xffffffff ) +#endif + ) { + if (ckWARN(WARN_PORTABLE)) + Perl_warner(aTHX_ WARN_PORTABLE, + "Binary number > 0b11111111111111111111111111111111 non-portable"); + } + *retlen = s - start; + return rnv; +} + +NV +Perl_scan_oct(pTHX_ char *start, STRLEN len, STRLEN *retlen) +{ + register char *s = start; + register NV rnv = 0.0; + register UV ruv = 0; + register bool overflowed = FALSE; + + for (; len-- && *s; s++) { + if (!(*s >= '0' && *s <= '7')) { + if (*s == '_' && len && *retlen + && (s[1] >= '0' && s[1] <= '7')) + { + --len; + ++s; + } + else { + /* Allow \octal to work the DWIM way (that is, stop scanning + * as soon as non-octal characters are seen, complain only iff + * someone seems to want to use the digits eight and nine). */ + if (*s == '8' || *s == '9') { + if (ckWARN(WARN_DIGIT)) + Perl_warner(aTHX_ WARN_DIGIT, + "Illegal octal digit '%c' ignored", *s); + } + break; + } + } + if (!overflowed) { + register UV xuv = ruv << 3; + + if ((xuv >> 3) != ruv) { + overflowed = TRUE; + rnv = (NV) ruv; + if (ckWARN_d(WARN_OVERFLOW)) + Perl_warner(aTHX_ WARN_OVERFLOW, + "Integer overflow in octal number"); + } + else + ruv = xuv | (*s - '0'); + } + if (overflowed) { + rnv *= 8.0; + /* If an NV has not enough bits in its mantissa to + * represent an UV this summing of small low-order numbers + * is a waste of time (because the NV cannot preserve + * the low-order bits anyway): we could just remember when + * did we overflow and in the end just multiply rnv by the + * right amount of 8-tuples. */ + rnv += (NV)(*s - '0'); + } + } + if (!overflowed) + rnv = (NV) ruv; + if ( ( overflowed && rnv > 4294967295.0) +#if UVSIZE > 4 + || (!overflowed && ruv > 0xffffffff ) +#endif + ) { + if (ckWARN(WARN_PORTABLE)) + Perl_warner(aTHX_ WARN_PORTABLE, + "Octal number > 037777777777 non-portable"); + } + *retlen = s - start; + return rnv; +} + +NV +Perl_scan_hex(pTHX_ char *start, STRLEN len, STRLEN *retlen) +{ + register char *s = start; + register NV rnv = 0.0; + register UV ruv = 0; + register bool overflowed = FALSE; + char *hexdigit; + + if (len > 2) { + if (s[0] == 'x') { + s++; + len--; + } + else if (len > 3 && s[0] == '0' && s[1] == 'x') { + s+=2; + len-=2; + } + } + + for (; len-- && *s; s++) { + hexdigit = strchr((char *) PL_hexdigit, *s); + if (!hexdigit) { + if (*s == '_' && len && *retlen && s[1] + && (hexdigit = strchr((char *) PL_hexdigit, s[1]))) + { + --len; + ++s; + } + else { + if (ckWARN(WARN_DIGIT)) + Perl_warner(aTHX_ WARN_DIGIT, + "Illegal hexadecimal digit '%c' ignored", *s); + break; + } + } + if (!overflowed) { + register UV xuv = ruv << 4; + + if ((xuv >> 4) != ruv) { + overflowed = TRUE; + rnv = (NV) ruv; + if (ckWARN_d(WARN_OVERFLOW)) + Perl_warner(aTHX_ WARN_OVERFLOW, + "Integer overflow in hexadecimal number"); + } + else + ruv = xuv | ((hexdigit - PL_hexdigit) & 15); + } + if (overflowed) { + rnv *= 16.0; + /* If an NV has not enough bits in its mantissa to + * represent an UV this summing of small low-order numbers + * is a waste of time (because the NV cannot preserve + * the low-order bits anyway): we could just remember when + * did we overflow and in the end just multiply rnv by the + * right amount of 16-tuples. */ + rnv += (NV)((hexdigit - PL_hexdigit) & 15); + } + } + if (!overflowed) + rnv = (NV) ruv; + if ( ( overflowed && rnv > 4294967295.0) +#if UVSIZE > 4 + || (!overflowed && ruv > 0xffffffff ) +#endif + ) { + if (ckWARN(WARN_PORTABLE)) + Perl_warner(aTHX_ WARN_PORTABLE, + "Hexadecimal number > 0xffffffff non-portable"); + } + *retlen = s - start; + return rnv; +} + +/* +=for apidoc grok_numeric_radix + +Scan and skip for a numeric decimal separator (radix). + +=cut + */ +bool +Perl_grok_numeric_radix(pTHX_ const char **sp, const char *send) +{ +#ifdef USE_LOCALE_NUMERIC + if (PL_numeric_radix_sv && IN_LOCALE) { + STRLEN len; + char* radix = SvPV(PL_numeric_radix_sv, len); + if (*sp + len <= send && memEQ(*sp, radix, len)) { + *sp += len; + return TRUE; + } + } + /* always try "." if numeric radix didn't match because + * we may have data from different locales mixed */ +#endif + if (*sp < send && **sp == '.') { + ++*sp; + return TRUE; + } + return FALSE; +} + +/* +=for apidoc grok_number + +Recognise (or not) a number. The type of the number is returned +(0 if unrecognised), otherwise it is a bit-ORed combination of +IS_NUMBER_IN_UV, IS_NUMBER_GREATER_THAN_UV_MAX, IS_NUMBER_NOT_INT, +IS_NUMBER_NEG, IS_NUMBER_INFINITY (defined in perl.h). If the value +of the number can fit an in UV, it is returned in the *valuep. + +=cut + */ +int +Perl_grok_number(pTHX_ const char *pv, STRLEN len, UV *valuep) +{ + const char *s = pv; + const char *send = pv + len; + const UV max_div_10 = UV_MAX / 10; + const char max_mod_10 = UV_MAX % 10 + '0'; + int numtype = 0; + int sawinf = 0; + + while (isSPACE(*s)) + s++; + if (*s == '-') { + s++; + numtype = IS_NUMBER_NEG; + } + else if (*s == '+') + s++; + + /* next must be digit or the radix separator or beginning of infinity */ + if (isDIGIT(*s)) { + /* UVs are at least 32 bits, so the first 9 decimal digits cannot + overflow. */ + UV value = *s - '0'; + /* This construction seems to be more optimiser friendly. + (without it gcc does the isDIGIT test and the *s - '0' separately) + With it gcc on arm is managing 6 instructions (6 cycles) per digit. + In theory the optimiser could deduce how far to unroll the loop + before checking for overflow. */ + int digit = *++s - '0'; + if (digit >= 0 && digit <= 9) { + value = value * 10 + digit; + digit = *++s - '0'; + if (digit >= 0 && digit <= 9) { + value = value * 10 + digit; + digit = *++s - '0'; + if (digit >= 0 && digit <= 9) { + value = value * 10 + digit; + digit = *++s - '0'; + if (digit >= 0 && digit <= 9) { + value = value * 10 + digit; + digit = *++s - '0'; + if (digit >= 0 && digit <= 9) { + value = value * 10 + digit; + digit = *++s - '0'; + if (digit >= 0 && digit <= 9) { + value = value * 10 + digit; + digit = *++s - '0'; + if (digit >= 0 && digit <= 9) { + value = value * 10 + digit; + digit = *++s - '0'; + if (digit >= 0 && digit <= 9) { + value = value * 10 + digit; + /* Now got 9 digits, so need to check + each time for overflow. */ + digit = *++s - '0'; + while (digit >= 0 && digit <= 9 + && (value < max_div_10 + || (value == max_div_10 + && *s <= max_mod_10))) { + value = value * 10 + digit; + digit = *++s - '0'; + } + if (digit >= 0 && digit <= 9) { + /* value overflowed. + skip the remaining digits, don't + worry about setting *valuep. */ + do { + s++; + } while (isDIGIT(*s)); + numtype |= + IS_NUMBER_GREATER_THAN_UV_MAX; + goto skip_value; + } + } + } + } + } + } + } + } + } + numtype |= IS_NUMBER_IN_UV; + if (valuep) + *valuep = value; + + skip_value: + if (GROK_NUMERIC_RADIX(&s, send)) { + numtype |= IS_NUMBER_NOT_INT; + while (isDIGIT(*s)) /* optional digits after the radix */ + s++; + } + } + else if (GROK_NUMERIC_RADIX(&s, send)) { + numtype |= IS_NUMBER_NOT_INT; + /* no digits before the radix means we need digits after it */ + if (isDIGIT(*s)) { + do { + s++; + } while (isDIGIT(*s)); + numtype |= IS_NUMBER_IN_UV; + if (valuep) { + /* integer approximation is valid - it's 0. */ + *valuep = 0; + } + } + else + return 0; + } + else if (*s == 'I' || *s == 'i') { + s++; if (*s != 'N' && *s != 'n') return 0; + s++; if (*s != 'F' && *s != 'f') return 0; + s++; if (*s == 'I' || *s == 'i') { + s++; if (*s != 'N' && *s != 'n') return 0; + s++; if (*s != 'I' && *s != 'i') return 0; + s++; if (*s != 'T' && *s != 't') return 0; + s++; if (*s != 'Y' && *s != 'y') return 0; + s++; + } + sawinf = 1; + } + else /* Add test for NaN here. */ + return 0; + + if (sawinf) { + numtype &= IS_NUMBER_NEG; /* Keep track of sign */ + numtype |= IS_NUMBER_INFINITY | IS_NUMBER_NOT_INT; + } else { + /* we can have an optional exponent part */ + if (*s == 'e' || *s == 'E') { + /* The only flag we keep is sign. Blow away any "it's UV" */ + numtype &= IS_NUMBER_NEG; + numtype |= IS_NUMBER_NOT_INT; + s++; + if (*s == '-' || *s == '+') + s++; + if (isDIGIT(*s)) { + do { + s++; + } while (isDIGIT(*s)); + } + else + return 0; + } + } + while (isSPACE(*s)) + s++; + if (s >= send) + return numtype; + if (len == 10 && memEQ(pv, "0 but true", 10)) { + if (valuep) + *valuep = 0; + return IS_NUMBER_IN_UV; + } + return 0; +} + +NV +S_mulexp10(NV value, I32 exponent) +{ + NV result = 1.0; + NV power = 10.0; + bool negative = 0; + I32 bit; + + if (exponent == 0) + return value; + else if (exponent < 0) { + negative = 1; + exponent = -exponent; + } + for (bit = 1; exponent; bit <<= 1) { + if (exponent & bit) { + exponent ^= bit; + result *= power; + } + power *= power; + } + return negative ? value / result : value * result; +} + +NV +Perl_my_atof(pTHX_ const char* s) +{ + NV x = 0.0; +#ifdef USE_LOCALE_NUMERIC + if (PL_numeric_local && IN_LOCALE) { + NV y; + + /* Scan the number twice; once using locale and once without; + * choose the larger result (in absolute value). */ + Perl_atof2(aTHX_ s, &x); + SET_NUMERIC_STANDARD(); + Perl_atof2(aTHX_ s, &y); + SET_NUMERIC_LOCAL(); + if ((y < 0.0 && y < x) || (y > 0.0 && y > x)) + return y; + } + else + Perl_atof2(aTHX_ s, &x); +#else + Perl_atof2(aTHX_ s, &x); +#endif + return x; +} + +char* +Perl_my_atof2(pTHX_ const char* orig, NV* value) +{ + NV result = 0.0; + bool negative = 0; + char* s = (char*)orig; + char* send = s + strlen(orig) - 1; + bool seendigit = 0; + I32 expextra = 0; + I32 exponent = 0; + I32 i; +/* this is arbitrary */ +#define PARTLIM 6 +/* we want the largest integers we can usefully use */ +#if defined(HAS_QUAD) && defined(USE_64_BIT_INT) +# define PARTSIZE ((int)TYPE_DIGITS(U64)-1) + U64 part[PARTLIM]; +#else +# define PARTSIZE ((int)TYPE_DIGITS(U32)-1) + U32 part[PARTLIM]; +#endif + I32 ipart = 0; /* index into part[] */ + I32 offcount; /* number of digits in least significant part */ + + /* sign */ + switch (*s) { + case '-': + negative = 1; + /* fall through */ + case '+': + ++s; + } + + part[0] = offcount = 0; + if (isDIGIT(*s)) { + seendigit = 1; /* get this over with */ + + /* skip leading zeros */ + while (*s == '0') + ++s; + } + + /* integer digits */ + while (isDIGIT(*s)) { + if (++offcount > PARTSIZE) { + if (++ipart < PARTLIM) { + part[ipart] = 0; + offcount = 1; /* ++0 */ + } + else { + /* limits of precision reached */ + --ipart; + --offcount; + if (*s >= '5') + ++part[ipart]; + while (isDIGIT(*s)) { + ++expextra; + ++s; + } + /* warn of loss of precision? */ + break; + } + } + part[ipart] = part[ipart] * 10 + (*s++ - '0'); + } + + /* decimal point */ + if (GROK_NUMERIC_RADIX((const char **)&s, send)) { + if (isDIGIT(*s)) + seendigit = 1; /* get this over with */ + + /* decimal digits */ + while (isDIGIT(*s)) { + if (++offcount > PARTSIZE) { + if (++ipart < PARTLIM) { + part[ipart] = 0; + offcount = 1; /* ++0 */ + } + else { + /* limits of precision reached */ + --ipart; + --offcount; + if (*s >= '5') + ++part[ipart]; + while (isDIGIT(*s)) + ++s; + /* warn of loss of precision? */ + break; + } + } + --expextra; + part[ipart] = part[ipart] * 10 + (*s++ - '0'); + } + } + + /* combine components of mantissa */ + for (i = 0; i <= ipart; ++i) + result += S_mulexp10((NV)part[ipart - i], + i ? offcount + (i - 1) * PARTSIZE : 0); + + if (seendigit && (*s == 'e' || *s == 'E')) { + bool expnegative = 0; + + ++s; + switch (*s) { + case '-': + expnegative = 1; + /* fall through */ + case '+': + ++s; + } + while (isDIGIT(*s)) + exponent = exponent * 10 + (*s++ - '0'); + if (expnegative) + exponent = -exponent; + } + + /* now apply the exponent */ + exponent += expextra; + result = S_mulexp10(result, exponent); + + /* now apply the sign */ + if (negative) + result = -result; + *value = result; + return s; +} + |